drm/i915: Move modeset state verifier calls.

The modeset state verifier no longer has full access to the hardware,
instead it should only verify affected crtc's.

Looking for disabled stuff can be verified immediately after all crtc
disables have completed, while each enabled crtc can be verified right
after being enabled.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1458741487-23801-3-git-send-email-maarten.lankhorst@linux.intel.com


Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
[mlankhorst: check -> verify]